1. Field of the Invention
The invention relates generally to cutting machinery and more specifically to high-speed contour foam sponge cutting machines.
2. Description of the Related Art
Cutting machines are able to cut in two planes, but use two different blades to do so and cannot use a single blade to accomplish cuts in different planes. When cutting a contour into a piece of foam, the contour is established by cutting in one plane, and then moving the foam into a different position so that the next blade can cut in another plane. Most finished foam products require two operations for the cutting to be complete. This is often done with two machines, with one cutting in one direction and the second cutting in another. As an example, the first machine can cut regular horizontal straight sheets in a stack arrangement with a horizontal blade, and a second machine can cut contours out of these sheets with a vertical blade. As another example, a horizontal contour blade can cut contours in horizontal logs, and a second machine or operation is needed to cut the logs to a desired length. This requires two machines with two operations, which means that extra space and storage are needed between the two machines. Extra handling of the foam is also required, which reduces the consistency and accuracy of cuts.
Combination machines with two cutting blades, such as machines that use vibrating blades as cutting devices, may have slow speed capabilities that are not suitable for high volume production. Another known machine has two separate cutting units, each with its own cutting blade, but lacks a way to secure the foam block during the cutting process. The distance between the two cutting blades may be approximately four feet. This can cause problems because, during transport from the first blade to the second, the foam can move from its original position, particularly since foam is flexible and may shift in position, and the second cut in the cutting program may not register properly with the first cut. This can result in cuts that are misaligned. Users have tried to prevent the foam blocks from moving by, for example, taping the block together, or putting additional foam blocks on each side of the original block to prevent movements, but these solutions do not provide secure holds. Manufacturers of contour cutting machines also have provided additional block guidance systems, but these are installed on the sides of the block and not the front and back where the holding together is most needed. Therefore, a solution is needed for increased precision during cutting, and for preventing movement of the foam block that is to be cut, such that more accuracy and consistency between the horizontal and vertical cuts can be achieved. Since the foam block moves in a front to back direction, rapid acceleration and/or deceleration results in the block wiggling, especially towards the top of the block. Block guidance systems on the sides or top of the block as known in the prior art are not sufficient for supporting the foam block to prevent this movement, since additional support is needed in the front and back for that restriction of movement.
Continuous band knife machines as known in the art may have drive wheels that are in contact with the band knife only for a quarter of the wheel's circumference. The wheels may be coated with rubber or a polyurethane material to ensure good friction and positive drive. However, due to the high tension and the narrow width of the blade of the band knife, the drive wheels may wear out in a short amount of time, and need to be repaired or replaced. Thus, a solution is needed for extending the life of the drive wheels.
The aspects or the problems and the associated solutions presented in this section could be or could have been pursued; they are not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches presented in this section qualify as prior art merely by virtue of their presence in this section of the application.